1. Field of the Invention
The present invention relates to uses of biodiesel production byproducts and other materials related to biomass, including the conversion of glycerol from biodiesel production to allyl alcohol, for use as in the synthesis of polymers and carbon-based products.
2. Related Art
As biomass is the only sustainable carbon resource and fossil resources are predicted to be exhausted in a few decades, biomass refinery processes must be developed to replace petroleum feedstocks. This has directed many researchers' interests to the use of biomass as a source of energy and chemical intermediates. The processing technology for fossil raw materials is well known and developed, but it differs radically from bio-feedstocks chemical transformations. A combined effort of companies and academic laboratories is needed to make biomass competitive with fossil raw materials.
Biodiesel produced from soybean oil generates large amounts of glycerol as a byproduct which is currently in oversupply. There is currently strong interest in developing ways to produce industrially important chemicals from renewable biological sources rather than petroleum, such as allyl alcohol. Allyl alcohol is currently made from propylene, which is a petroleum feedstock. Allyl alcohol is often used as a starting material in making various polymers, pharmaceuticals, pesticides and other allyl-substituted compounds
Biomass-derived raw materials contain excess functionality, usually having a high oxygen content, which makes them problematical for use as fuels and petrochemicals. The challenge in this field, therefore, is to develop methods to control the functionality in the final products, especially to remove oxygen and replace it with hydrogen and/or carbon-carbon multiple bonds. Reasonable targets for such processes involve dehydration or deoxygenation, which can lead to the formation of olefins or cyclic anhydride derivatives.
Currently there is no industrial process for the large-scale preparation of allyl alcohol from glycerol. As described below, the most effective synthesis in the open literature, which was published many years ago, is not very adequate. This procedure, described in Organic Syntheses, Coll. Vol. 1, p. 42 (1941); Vol. 1, p. 15 (1921), requires heating of glycerol and acid to produce allyl alcohol. However, as it notes, “slow heating causes charring and formation of much acrolein, and thus gives a very low yield of allyl alcohol.” Furthermore, more rapid heating is somewhat irreproducible and does not give yields above 50%. Thus, it would be beneficial to provide a method for carrying out this synthesis that is more reliable and that provides a pure product of allyl alcohol in sufficient yield quantities.